Physical activity and lung function decline in adults with asthma: The HUNT Study

People with asthma may seek advice about physical activity. However, the benefits of leisure time physical activity on lung function are unclear. We investigated the association between leisure time physical activity and lung function decline in adults with asthma.

In a population-based cohort study in Norway, we used multiple linear regressions to estimate the annual mean decline in lung function (and 95% CI) in 1329 people with asthma over a mean follow-up of 11.6 years. The durations of light and hard physical activity per week in the last year were collected by questionnaire. Inactive participants did not report any light or hard activity, while active participants reported light or hard activity.

The mean decline in forced expiratory volume in 1 s (FEV₁ ) was 37 mL/year among inactive participants and 32 mL/year in active participants (difference: -5 mL/year (95% CI: -13 to 3)). The mean decline in forced vital capacity (FVC) was 33 mL/year among inactive participants and 31 mL/year in active participants (difference: -2 mL/year (95% CI: -11 to 7)). The mean decline in FEV₁ /FVC ratio was 0.36%/year among inactive participants and 0.22%/year in active participants (difference: -0.14%/year (95% CI: -0.27 to -0.01)). The mean decline in peak expiratory flow (PEF) was 14 mL/year among the inactive participants and 10 mL/year in active participants (difference: -4 mL/year (95% CI: -9 to 1)).

We observed slightly less decline in lung function in physically active than inactive participants with asthma, particularly for FEV₁ , FEV₁ /FVC ratio and PEF.